// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_POOL_H_
#define NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_POOL_H_

#include <memory>
#include <string>

#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "net/base/host_port_pair.h"
#include "net/base/net_export.h"
#include "net/http/http_auth.h"
#include "net/http/http_response_info.h"
#include "net/http/proxy_client_socket.h"
#include "net/socket/client_socket_pool.h"
#include "net/socket/client_socket_pool_base.h"
#include "net/socket/ssl_client_socket.h"
#include "net/spdy/spdy_session.h"

namespace net {

class HttpAuthCache;
class HttpAuthHandlerFactory;
class HttpProxyClientSocketWrapper;
class ProxyDelegate;
class SSLClientSocketPool;
class SSLSocketParams;
class SpdySessionPool;
class SpdyStream;
class TransportClientSocketPool;
class TransportSocketParams;

// HttpProxySocketParams only needs the socket params for one of the proxy
// types.  The other param must be NULL.  When using an HTTP Proxy,
// |transport_params| must be set.  When using an HTTPS Proxy, |ssl_params|
// must be set.
class NET_EXPORT_PRIVATE HttpProxySocketParams
    : public base::RefCounted<HttpProxySocketParams> {
public:
    HttpProxySocketParams(
        const scoped_refptr<TransportSocketParams>& transport_params,
        const scoped_refptr<SSLSocketParams>& ssl_params,
        const std::string& user_agent,
        const HostPortPair& endpoint,
        HttpAuthCache* http_auth_cache,
        HttpAuthHandlerFactory* http_auth_handler_factory,
        SpdySessionPool* spdy_session_pool,
        bool tunnel,
        ProxyDelegate* proxy_delegate);

    const scoped_refptr<TransportSocketParams>& transport_params() const
    {
        return transport_params_;
    }
    const scoped_refptr<SSLSocketParams>& ssl_params() const
    {
        return ssl_params_;
    }
    const std::string& user_agent() const { return user_agent_; }
    const HostPortPair& endpoint() const { return endpoint_; }
    HttpAuthCache* http_auth_cache() const { return http_auth_cache_; }
    HttpAuthHandlerFactory* http_auth_handler_factory() const
    {
        return http_auth_handler_factory_;
    }
    SpdySessionPool* spdy_session_pool()
    {
        return spdy_session_pool_;
    }
    const HostResolver::RequestInfo& destination() const;
    bool tunnel() const { return tunnel_; }

    ProxyDelegate* proxy_delegate() const
    {
        return proxy_delegate_;
    }

private:
    friend class base::RefCounted<HttpProxySocketParams>;
    ~HttpProxySocketParams();

    const scoped_refptr<TransportSocketParams> transport_params_;
    const scoped_refptr<SSLSocketParams> ssl_params_;
    SpdySessionPool* spdy_session_pool_;
    const std::string user_agent_;
    const HostPortPair endpoint_;
    HttpAuthCache* const http_auth_cache_;
    HttpAuthHandlerFactory* const http_auth_handler_factory_;
    const bool tunnel_;
    ProxyDelegate* proxy_delegate_;

    DISALLOW_COPY_AND_ASSIGN(HttpProxySocketParams);
};

// HttpProxyConnectJob optionally establishes a tunnel through the proxy
// server after connecting the underlying transport socket.
class HttpProxyConnectJob : public ConnectJob {
public:
    HttpProxyConnectJob(const std::string& group_name,
        RequestPriority priority,
        ClientSocketPool::RespectLimits respect_limits,
        const scoped_refptr<HttpProxySocketParams>& params,
        const base::TimeDelta& timeout_duration,
        TransportClientSocketPool* transport_pool,
        SSLClientSocketPool* ssl_pool,
        Delegate* delegate,
        NetLog* net_log);
    ~HttpProxyConnectJob() override;

    // ConnectJob methods.
    LoadState GetLoadState() const override;

    void GetAdditionalErrorState(ClientSocketHandle* handle) override;

private:
    // Begins the tcp connection and the optional Http proxy tunnel.  If the
    // request is not immediately servicable (likely), the request will return
    // ERR_IO_PENDING. An OK return from this function or the callback means
    // that the connection is established; ERR_PROXY_AUTH_REQUESTED means
    // that the tunnel needs authentication credentials, the socket will be
    // returned in this case, and must be release back to the pool; or
    // a standard net error code will be returned.
    int ConnectInternal() override;

    void OnConnectComplete(int result);

    int HandleConnectResult(int result);

    std::unique_ptr<HttpProxyClientSocketWrapper> client_socket_;

    std::unique_ptr<HttpResponseInfo> error_response_info_;

    DISALLOW_COPY_AND_ASSIGN(HttpProxyConnectJob);
};

class NET_EXPORT_PRIVATE HttpProxyClientSocketPool
    : public ClientSocketPool,
      public HigherLayeredPool {
public:
    typedef HttpProxySocketParams SocketParams;

    HttpProxyClientSocketPool(int max_sockets,
        int max_sockets_per_group,
        TransportClientSocketPool* transport_pool,
        SSLClientSocketPool* ssl_pool,
        NetLog* net_log);

    ~HttpProxyClientSocketPool() override;

    // ClientSocketPool implementation.
    int RequestSocket(const std::string& group_name,
        const void* connect_params,
        RequestPriority priority,
        RespectLimits respect_limits,
        ClientSocketHandle* handle,
        const CompletionCallback& callback,
        const BoundNetLog& net_log) override;

    void RequestSockets(const std::string& group_name,
        const void* params,
        int num_sockets,
        const BoundNetLog& net_log) override;

    void CancelRequest(const std::string& group_name,
        ClientSocketHandle* handle) override;

    void ReleaseSocket(const std::string& group_name,
        std::unique_ptr<StreamSocket> socket,
        int id) override;

    void FlushWithError(int error) override;

    void CloseIdleSockets() override;

    int IdleSocketCount() const override;

    int IdleSocketCountInGroup(const std::string& group_name) const override;

    LoadState GetLoadState(const std::string& group_name,
        const ClientSocketHandle* handle) const override;

    std::unique_ptr<base::DictionaryValue> GetInfoAsValue(
        const std::string& name,
        const std::string& type,
        bool include_nested_pools) const override;

    base::TimeDelta ConnectionTimeout() const override;

    // LowerLayeredPool implementation.
    bool IsStalled() const override;

    void AddHigherLayeredPool(HigherLayeredPool* higher_pool) override;

    void RemoveHigherLayeredPool(HigherLayeredPool* higher_pool) override;

    // HigherLayeredPool implementation.
    bool CloseOneIdleConnection() override;

private:
    typedef ClientSocketPoolBase<HttpProxySocketParams> PoolBase;

    class HttpProxyConnectJobFactory : public PoolBase::ConnectJobFactory {
    public:
        HttpProxyConnectJobFactory(TransportClientSocketPool* transport_pool,
            SSLClientSocketPool* ssl_pool,
            NetLog* net_log);

        // ClientSocketPoolBase::ConnectJobFactory methods.
        std::unique_ptr<ConnectJob> NewConnectJob(
            const std::string& group_name,
            const PoolBase::Request& request,
            ConnectJob::Delegate* delegate) const override;

        base::TimeDelta ConnectionTimeout() const override;

    private:
        TransportClientSocketPool* const transport_pool_;
        SSLClientSocketPool* const ssl_pool_;
        NetLog* net_log_;
        base::TimeDelta timeout_;

        DISALLOW_COPY_AND_ASSIGN(HttpProxyConnectJobFactory);
    };

    TransportClientSocketPool* const transport_pool_;
    SSLClientSocketPool* const ssl_pool_;
    PoolBase base_;

    DISALLOW_COPY_AND_ASSIGN(HttpProxyClientSocketPool);
};

} // namespace net

#endif // NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_POOL_H_
